1. Field of the Invention
This invention relates in general to circuit arrangements for checking transmission rates which uses counters.
2. Description of the Prior Art
So as to avoid overload in the transmission of cells in broadband switching systems, it has been proposed in the article International Zurich Seminar on Digital Communications, March 1986, entitled "New Directions In Communications" A3.1 through A3.8, J. B. Turner to allocate a forward-backward counter in a switching node to every subscriber equipment which is connected and the forward backward counter counts the cells transmitted by the respective subscriber equipment and lowers the counter reading corresponding to the transmission rate defined by respective subscriber equipment at specific times. When the momentary counter reading exceeds a value for the respective subscriber equipment then the switching node recognizes it as an overload (leaky bucket method).
Another circuit arrangement for preventing overload in a broadband switching system is described in German published application 37 32 937. Instead of a forward-backward counter, two forward counters in this circuit arrangement are assigned in a switching node to every subscriber equipment which is connected such that a first counter counts the cells sent by the respective subscriber equipment and the other counter calculates the connection time that elapses during the existing call. The two counters are connected to a means which checks the observation of the maximum bit rate defined by the respective subscriber equipment based on the relationship between the counter readings.